Due to the nature of the system, particularly
complicated but non-critical driving condi-
tions may also cause Brake Assist to inter-
vene.
If adaptive Brake Assist is not available due to
a malfunction in the radar sensor system, the
brake system remains available with full
brake boosting effect and BAS.
ESP®(Electronic Stability Program)
General notes
iObserve the "Important safety notes" sec-
tion (
Ypage 67).
ESP
®monitors driving stability and traction,
i.e. power transmission between the tires and
the road surface.
If ESP
®detects that the vehicle is deviating
from the direction desired by the driver, one
or more wheels are braked to stabilize the
vehicle. The engine output is also modified to
keep the vehicle on the desired course within
physical limits. ESP
®assists the driver when
pulling away on wet or slippery roads. ESP®
can also stabilize the vehicle during braking.
ETS/4ETS (Electronic Traction System)
iObserve the "Important safety notes" sec-
tion (
Ypage 67).
ETS traction control is part of ESP
®. On vehi-
cles with 4MATIC, 4ETS is part of ESP®.
Traction control brakes the drive wheels indi-
vidually if they spin. This enables you to pull
away and accelerate on slippery surfaces, for
example if the road surface is slippery on one side. In addition, more drive torque is trans-
ferred to the wheel or wheels with traction.
Traction control remains active, even if you
deactivate ESP
®.
Important safety notes
iObserve the "Important safety notes" sec-
tion (
Ypage 67).
GWARNING
If ESP
®is malfunctioning, ESP®is unable to
stabilize the vehicle. Additionally, further driv-
ing safety systems are deactivated. This
increases the risk of skidding and an accident.
Drive on carefully. Have ESP
®checked at a
qualified specialist workshop.
If the å ESP®OFF warning lamp lights up
continuously, ESP®is deactivated.
If the ÷ ESP
®warning lamp lights up con-
tinuously, ESP®is not available due to a mal-
function.
Observe the information on warning lamps
(
Ypage 296) and display messages which
may be shown in the instrument cluster
(
Ypage 258).
Only use wheels with the recommended tire
sizes. Only then will ESP
®function properly.
Characteristics of ESP®
General information
If the ÷ ESP warning lamp goes out before
beginning the journey, ESP
®is automatically
active.
If ESP
®intervenes, the ÷ESP®warning
lamp flashes in the instrument cluster.
If ESP
®intervenes:
XDo not deactivate ESP®under any circum-
stances.
XOnly depress the accelerator pedal as far as
necessary when pulling away.
XAdapt your driving style to suit the prevail-
ing road and weather conditions.
ECO start/stop function
The ECO start/stop function switches the
engine off automatically when the vehicle
stops moving. The engine starts automati-
cally when the driver wants to pull away again.
Driving safet ysystem s73
Safety
Z
Useful information
i
This Operator's Manual describes all
models and all standard and optional equip-
ment of your vehicle available at the time of
publication of the Operator's Manual.
Country-specific differences are possible.
Please note that your vehicle may not be
equipped with all features described. This
also applies to safety-related systems and
functions.
iRead the information on qualified special-
ist workshops (
Ypage 27).
SmartKey
Important safety notes
GWARNING
If children are left unsupervised in the vehicle,
they could:
Ropen the doors, thus endangering other
people or road users.
Rget out and disrupt traffic.
Roperate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
Rrelease the parking brake.
Rshifting the automatic transmission out of
park position P
RStart the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
GWARNING
If you attach heavy or large objects to the
SmartKey, the SmartKey could be uninten-
tionally turned in the ignition lock. This could
cause the engine to be switched off. There is a risk of an accident.
Do not attach any heavy or large objects to theSmartKey. Remove any bulky key rings before
inserting the SmartKey into the ignition lock.
!Keep the SmartKey away from strong
magnetic fields. Otherwise, the remote
control function could be affected.
Strong magnetic fields can occur in the
vicinity of powerful electrical installations.
Do not keep the SmartKey:
Rwith electronic devices, e.g. a mobile
phone or another SmartKey.
Rwith metallic objects, e.g. coins or metal
foil.
Rinside metallic objects, e.g. a metal case.
This can affect the functionality of the
SmartKey.
Vehicles with KEYLESS-GO start function:
do not keep the SmartKey in the cargo com-
partment. Otherwise, the SmartKey may not
be detected, e.g. when starting the engine
using the Start/Stop button.
A check which periodically establishes a radio
connection between the vehicle and the
SmartKey determines whether a valid Smart-
Key is in the vehicle. This occurs, for example:
Rwhen starting the engine
Rwhilst driving
Rwhen the external door handles are
touched
Rduring convenience closing
82SmartKey
Opening and closing
Useful information............................152
Notes on breaking-in a new vehi-
cle ....................................................... 152
Driving ............................................... 152
DYNAMIC SELECT switch .................161
Automatic transmission ...................161
Refueling ............................................ 169
Parking ............................................... 172
Driving tips ........................................ 176
Driving systems ................................ 181
Towing a trailer ................................. 227
151
Driving and parking
GWARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or not at all. This could affect, for example, the power steering and the brake
boosting effect. You will require considerably
more effort to steer and brake. There is a risk
of an accident.
Do not switch off the ignition while driving.
GWARNING
If the parking brake has not been fully
released when driving, the parking brake can:
Roverheat and cause a fire
Rlose its hold function.
There is a risk of fire and an accident. Release
the parking brake fully before driving off.
!Do not warm up the engine with the vehi-
cle stationary. Drive off immediately. Avoid
high engine speeds and driving at full throt-
tle until the engine has reached its operat-
ing temperature.
Only shift the automatic transmission to
the desired drive position when the vehicle
is stationary.
Where possible, avoid spinning the drive
wheels when pulling away on slippery
roads. You could otherwise damage the
drive train.
SmartKey positions
SmartKey
gTo remove the SmartKey
1Power supply for some consumers, such
as the windshield wipers
2Ignition (power supply for all consumers)
and drive position
3To start the engine
iThe SmartKey can be turned in the igni-
tion lock even if it is not the correct Smart- Key for the vehicle. The ignition is not
switched on. The engine cannot be started.
Start/Stop button
General notes
When you insert the Start/Stop button into
the ignition lock, the system needs approx-
imately two seconds recognition time. You
can then use the Start/Stop button.
Pressing the Start/Stop button several times
in succession corresponds to the different
key positions in the ignition lock. This is only
the case if you are not depressing the brake
pedal.
If you depress the brake pedal and press the
Start/Stop button, the engine starts immedi-
ately.
A check which periodically establishes a radio
connection between the vehicle and the
SmartKey determines whether a valid Smart-
Key is in the vehicle. This occurs, for example,
when starting the engine.
Driving153
Driving and parking
Z
Removing the Start/Stop button
You can remove the Start/Stop button from
the ignition lock and start the vehicle as nor-
mal using the SmartKey.
It is only possible to switch between Start/
Stop button mode and SmartKey operation
when the transmission is in positionP.
XRemove Start/Stop button:from ignition
lock ;.
You do not have to remove the Start/Stop
button from the ignition lock when you leave
the vehicle. You should, however, always take
the SmartKey with you when leaving the vehi-
cle. As long as the SmartKey is in the vehicle:
Rthe vehicle can be started using the Start/
Stop button
Rthe electrically powered equipment can be
operated
Starting the engine
Important safety notes
GWARNING
If children are left unsupervised in the vehicle,
they could:
Ropen the doors, thus endangering other
people or road users.
Rget out and disrupt traffic.
Roperate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
Rrelease the parking brake.
Rshifting the automatic transmission out of
park position P
RStart the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
GWARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Inhaling
these exhaust gases leads to poisoning. There
is a risk of fatal injury. Therefore never leave
the engine running in enclosed spaces with-
out sufficient ventilation.
GWARNING
Flammable materials introduced through
environmental influence or by animals can
ignite if in contact with the exhaust system or
parts of the engine that heat up. There is a risk
of fire.
Carry out regular checks to make sure that
there are no flammable foreign materials in
the engine compartment or in the exhaust
system.
!Do not depress the accelerator when
starting the engine.
General notes
The catalytic converter is preheated for up to
30 seconds after a cold start. The sound of
the engine may change during this time.
Automatic transmission
XShift the transmission to position P
(
Ypage 162).
The transmission position display in the
multifunction display shows
P (
Ypage 163).
iYou can start the engine in transmission
position Pand N.
Starting procedure with the SmartKey
To start the engine using the SmartKey
instead of the Start/Stop button, pull the
Start/Stop button out of the ignition lock.
XTurn the SmartKey to position 3in the igni-
tion lock and release it as soon as the
engine is running (
Ypage 153).
Driving155
Driving and parking
Z
Make sure that the engine cannot be started
via your smartphone before carrying out
maintenance or repairs. You can prevent an
engine start via your smartphone, for exam-
ple, if you:
Rswitch on the hazard warning lamps
Rdo not lock the doors
Ropen the hood
Pulling away
General notes
GWARNING
If the engine speed is above the idling speed
and you engage transmission position Dor R,
the vehicle could pull away suddenly. There is
a risk of an accident.
When engaging transmission position Dor R,
always firmly depress the brake pedal and do not simultaneously accelerate.
Depress the accelerator carefully when pull-
ing away.
The vehicle locks centrally once you have
pulled away. The locking knobs in the doors
drop down.
You can open the doors from the inside at any
time.
You can also deactivate the automatic locking
feature, see the Digital Operator's Manual.
It is only possible to shift the transmission
from position Pto the desired position if you
depress the brake pedal. Only then is the
parking lock released. If you do not depress
the brake pedal, the DIRECT SELECT lever can
still be moved but the parking lock remains
engaged.
iUpshifts take place at higher engine
speeds after a cold start. This helps the
catalytic converter to reach its operating
temperature more quickly.
Information on the automatic release of the
electric parking brake (
Ypage 174).
Pulling away with a trailer
To ensure that you do not roll backwards
when pulling away on an uphill slope, engage
the electric parking brake.
XPress and hold handle :.
The electric parking brake continues to
brake and prevent the vehicle from rolling
backwards.
The red F(USA only) or !(Canada
only) indicator lamp in the instrument clus-
ter remains on.
XDepress the accelerator pedal.
XAs soon as the vehicle/trailer combination
is held by the driving force of the engine,
release lever :.
the electric parking brake is released.
The red F(USA only) or !(Canada
only) indicator lamp in the instrument clus-
ter goes out.
For further information on the electric parking
brake, see (
Ypage 174).
Hill start assist
Hill start assist helps you when pulling away
forwards or in reverse on an uphill gradient. It
holds the vehicle for a short time after you
have removed your foot from the brake pedal.
This gives you enough time to move your foot
from the brake pedal to the accelerator pedal
and to depress it before the vehicle begins to
roll.
Driving157
Driving and parking
Z
GWARNING
After a short time, hill start assist will no lon-
ger brake your vehicle and it could roll away.
There is a risk of an accident and injury.
Therefore, quickly move your foot from the
brake pedal to the accelerator pedal. Never
leave the vehicle when it is held by hill start
assist.
Hill start assist is not active if:
Ryou are pulling away on a level road or on a downhill gradient.
Rthe transmission is in position N.
Rthe electric parking brake is applied.
RESP®is malfunctioning.
ECO start/stop function
Introduction
The ECO start/stop function switches the
engine off automatically if the vehicle is stop-
ped under certain conditions.
The engine starts automatically when the
driver wants to pull away again. The ECO
start/stop function thereby helps you to
reduce the fuel consumption and emissions
of your vehicle.
Important safety notes
GWARNING
If the engine is switched off automatically and
you exit the vehicle, the engine is restarted
automatically. The vehicle may begin moving.
There is a risk of accident and injury.
If you wish to exit the vehicle, always turn off
the ignition and secure the vehicle against
rolling away.
General notes
:ECO start/stop display
The ECO start/stop function is activated
whenever you start the engine using the
SmartKey or the Start/Stop button.
If the engine has been switched off automat-
ically by the ECO start/stop function, the
è ECO symbol is shown in the multifunc-
tion display.
Automatic engine switch-off
If the vehicle is braked to a standstill in Dor N,
the ECO start/stop function switches off the
engine automatically.
The ECO start/stop function is operational
when:
Rthe indicator lamp in the ECO button is lit
green.
Rthe outside temperature is within the range that is suitable for the system.
Rthe engine is at normal operating temper-
ature.
Rthe set temperature for the vehicle interior
has been reached.
Rthe battery is sufficiently charged.
Rthe system detects that the windshield is
not fogged up when the air-conditioning
system is switched on.
Rthe hood is closed.
Rthe driver's door is closed and the driver's
seat belt is fastened.
All of the vehicle's systems remain active
when the engine is stopped automatically.
The HOLD function can also be activated if the
engine has been switched off automatically. It
is then not necessary to continue applying the
brakes during the automatic stop phase.
158Driving
Driving and parking
When you depress the accelerator pedal, the
engine starts automatically and the braking
effect of the HOLD function is deactivated.
Automatic engine switch-off can take place a
maximum of four times in a row (initial stop,
then three subsequent stops).
Automatic engine start
The engine starts automatically if:
Ryou switch off the ECO start/stop function
by pressing the ECO button
Ryou switch to drive programS+
Rin transmission positionDor Nthe brake
pedal is released and the HOLD function is
not active
Ryou depress the accelerator pedal
Ryou engage reverse gear R
Ryou move the transmission out of position
P
Ryou unfasten your seat belt or open the
driver's door
Rthe vehicle starts to roll
Rthe brake system requires this
Rthe temperature in the vehicle interior devi-
ates from the set range
Rthe system detects moisture on the wind-
shield when the air-conditioning system is
switched on
Rthe battery's condition of charge is too low
Shifting the transmission to position Pdoes
not start the engine.
Deactivating or activating the ECO
start/stop function
XTo deactivate: press ECO button :.
Indicator lamp ;goes out.
XTo activate: press ECO button :.
Indicator lamp ;lights up.
If indicator lamp ;is off, the ECO start/stop
function has been deactivated manually or as
the result of a malfunction. The engine will
then not be switched off automatically when
the vehicle stops.
Selecting drive program S+deactivates the
ECO start/stop function. If you press ECO
button :, the ECO start/stop function is
activated.
Driving159
Driving and parking
Z